Tony Blair has apparently admitted that the invasion of Iraq by the United States and Britain was a disaster.

The Prime Minister gave the frank assessment of his decision to go to war in an interview with Sir David Frost on Al Jazeera’s new English-language channel.

Tony Blair

Opposition MPs seized on the comment as evidence that Mr Blair has finally accepted that his strategy in the Middle Eastern state had failed.

But Downing Street insisted that Mr Blair’s views had been misrepresented and that it was “disingenuous” to portray it as an admission. It later played down the comment as a “straightforward slip of the tongue”.

During the interview, Sir David suggested that the West’s intervention in Iraq had “so far been pretty much of a disaster”.

Mr Blair replied: “It has, but you see what I say to people is why is it difficult in Iraq? It’s not difficult because of some accident in planning, it’s difficult because there’s a deliberate strategy – al Qaida with Sunni insurgents on one hand, Iranian-backed elements with Shia militias on the other – to create a situation in which the will of the majority for peace is displaced by the will of the minority for war.”

Reacting to his comments, Liberal Democrat leader Sir Menzies Campbell said the Prime Minister should now apologise for his actions.

He said: “At long last the enormity of the decision to take military action against Iraq is being accepted by the Prime Minister. It could hardly be otherwise as the failure of strategy becomes so clear.

“If the Prime Minister accepts that it is a ‘disaster’ then surely Parliament and the British people who were given a flawed prospectus are entitled to an apology.”

A Downing Street spokeswoman said Mr Blair did not believe that the violence in Iraq had been a disaster. “He was simply acknowledging the question in a polite way before going on to explain his view. To portray it as some kind of admission is completely disingenuous,” the spokeswoman told the BBC.